Method and apparatus for wire forming



F. 0. DE MHLLAR March 18, 1941.

METHOD AND APFARATUS FOR WIRE FORMING Filed Jan. 16, 1959 2 Sheets-Sheet 1 March 18, 1941. F. 0. DE MILLAR 2,235,698

METHOD AND APPARATUS FOR WIRE FORMING Filed Jan. 16, 1939 2 Sheets-Sheet 2 INVENTOR BY Z 2 ATTORNEY Patented Mar. 18, 1941 PATENT OFFlCE METHOD AND APPARATUS FOR WIRE FORMING Floyd 0. De Millar,

Elastic Knitted Wire Rhode Island Warwick, R. 1., assignor to Co. Inc., a corporation of Application January 16, 1939, Serial No. 251,223

11 Claims.

My present invention relates to wire constructions, and has particular reference to a novel method and apparatus for forming wire into fiattened loops in strip form.

It is the principal object of my invention to provide a novel arrangement for forming a strip of wire loops.

Another object of my invention is to provide adjustments for changing the distance between wire loops, and for varying the shape of the wire loops.

It is a further object of my invention to pro vide a novel apparatus for forming the strips, which has a very high speed of manufacture.

An additional object of my invention is to provide a novel apparatus for forming wire coils in strips, which utilizes machine parts of relatively small cost, readily interchangeable to produce wire coils of different sizes, whereby the cost of manufacture is reduced.

Another object of my invention is to provide an automatic compensation for local variations in the resilience of the wire undergoing the forming operation.

With the above and other objects and advantageous features in view, my invention consists of a novel arrangement of parts and a novel method of operation more fully disclosed in the detailed description following, in conjunction with the accompanying drawings, and more specifically defined in the claims appended thereto.

Referring to the drawings:

Fig. 1 is a front elevation of the machine;

Fig. 2 is a side elevation thereof;

Fig. 3 is a top plan view thereof;

Fig. 4 is a perspective view of a helical coil of resilient wire which is used as a blank for forming a flattened loop strip;

Fig. 5 is a plan view of a flattened loop strip formed from the blank shown in Fig. 4;

Fig. 6 is a side view thereof;

Fig. '7 is a section on the line L- l of Fig. 3;

Fig. 8 is a section on the line 8--8 of Fig. 7;

Fig. 9 is an end view of a sleeve support;

Fig. 10 is a fragmentary detail, partly broken away, showing the tapering formation of the former slot;

Fig. 11 is a view on the line i l--l l of Fig. 10;

Fig. 12 is a section on the line 52-42 of Fig. 50 and Fig. 13 is a section on the line l3--l3 of Fig. 10.

My novel apparatus for forming strips of looped wire comprises a housing I!) having a transverse power shaft H rotatably mounted therein and 55 operated by means of a power driven pulley l2,

the power shaft H having a worm I3 positioned intermediate its ends for the purpose of rotating two resilient pressure pull rolls, as hereinafter described.

The housing H) has two openings It in its top portion l5 within which cylindrical sleeves it are positioned, the cylindrical sleeves having their lower ends stepped to seat on supports ll, see Fig. 9, which supports are provided with depending ears I8 bored to hingedly seat on the shaft II as disclosed in Fig. 8. Mounted within the sleeves 16 are suitable bearings for rotatable shafts l9 having worm wheels 20 keyed to their lower ends which mesh with the worm l3, and having stepped upper ends 2| upon which rolls 22 are firmly secured, the usual washers and lock bolts being preferably used. The rolls 22 are of resilient material, preferably rubber. for the purpose hereinafter disclosed, and the sleeves l6 loosely fit within the openings l4, adjusting screws 23 being mounted in the sides of the top portion 15 and projecting into the openings Hi to permit manual adjustment of the frictional pressure beween the two contacting resilient rolls 22.

The two resilient rolls are adapted to receive wire which has been twisted or turned into loop form, and to exert sufiicient pull on said wire, so as to pull the loops through a former device of predetermined shape, the resilience of the rolls providing a firm grip on the wire loops and compensating for local inequalities of the resilience of the wire.

A novel former device is utilized in conjunction with the pressure pull rolls, this device comprising a head 24 which includes a fixed jaw member 25 and a movable jaw member 26 pivotally secured to the head M, as by means of a screw 21, the twojaws being grooved on their contiguous faces to provide a forming die for the resilient wire coils, the illustrated forming die being circular at its entrance 28, see Fig. 1, and gradually tapering to an elliptical form 29, see Fig. 13, intermediate the ends thereof, and then to a slot 30 at the exit end, of generally rectangular form, whereby a helically wound coil of wire, such as indicated at 3| in Fig. 4, which passes through the former is gradually twisted against its own resilient tension so as to flatten the coil and present loops in succession to the pressure pull rolls 22, the width of the exit slot 30 controlling the drag or resistance of the strip of loops to pull by the pressure rolls. The pulling of the wire loops through the regulated slot produces a permanent deformation of the wire, and the loops assume a flat, laterally displaced relation as illustrated by the strip 32 in Figs. 5 and 6, the loops being in close lateral relation and preferably contacting. An adjusting screw 3|, see Fig. 10, is threadingly mounted in a suitable bearing 32 secured to or formed integral with the head 24, and has its end pressing against the movable jaw 26 so as to set the maximum width of the exit slot 30.

The former device is preferably releasably mounted on the housing In, so that different former devices suitable for different diameters of helical coils of wire may be interchanged, it being preferable to use a device with an entrance opening slightly greater than the crosssection of the helical coil of wire. The regulation of the width of the exit slot controls the spacing of the loops, a preferred spacing being as shown as A in the strip 32 illustrated in Fig. 5; the loops, however, may be closer together and lapped, or may be spread further apart, as desired.

The above described apparatus thus changes helical coils of wire into strips of laterally displaced wire loops, the distance between successive loops being regulated.

Although I have described the invention as utilizing resilient wire, any material in elongated form having the physical characteristics permitting coiling and knitting as described supra may be used, and the term wire as specified in the claims denotes such material broadly.

While I have described a specific constructional embodiment of my invention. it is obvious that changes in the pulling mechanism employed and in the character of the means for drawing successive loops of wire through the former device, and in the arrangement and operation of the former device parts, maybe made to suit the requirements for different resilient materials in strand form, without departing from the spirit and the scope of the invention as defined in the appended claims.

I claim:

1. In the manufacture of wire loops in strip form, the steps of feeding a wire coil to a former die, and exerting a resilient pull to draw wire loops through the former die.

2. In the manufacture of wire loops in strip form, the steps of feeding a wire coil to a former die, and exerting a resilient pull of regulated amount to draw wire loops through the former die.

3. In combination, a former device comprising a channel having an inlet opening for receiving a helicoil coil of wire, means therein for turning the loops of wire laterally, and an exit slot of reduced width, and means for exerting a resilient pull on said wire to draw said loops through said slot.

4. In combination, a former device comprising a channel having an inlet opening for receiving a helical coil of wire, means therein for turning the loops of wire laterally, and an exit slot of reduced adjustable width, and means for exerting a resilient pull on said wire to draw said loops through said slot.

5. In combination, a former device comprising a channel having an inlet opening for receiving a helical coil of wire, means therein for turning the loops of wire laterally, and an exit slot of reduced width, and means for exerting a resilient pull of regulated amount on said wire to draw said loops through said slot.

6. In combination, a former device comprising a channel having an inlet opening for receiving a helical coil of Wire, means therein for turning the loops of wire laterally, and an eXit slot of reduced width, and means for exerting a resilient pull on said wire to draw said loops through said slot, comprising contacting rolls of resilient material.

7. A former device for wire loops comprising a head having a fixed jaw, a movable jaw adjacent thereto, the contiguous sides of said jaws having grooves forming a die, said die having an inlet for receiving a helical coil of wire and being reduced in size to provide a narrow exit slot of a width corresponding to the width of the wire loops, and means for adjusting said movable jaw to change the width of the exit slot.

8. A former device for wire loops comprising a head having a fixed jaw, a movable jaw adjacent thereto pivotally hinged to said head, the contiguous sides of said jaws having grooves forming a die, said die having an inlet for receiving a helical coil of wire and being reduced in size to provide a narrow exit slot of a width corresponding to the width of the wire loops, and means for adjustably swinging said movable jaw to change the width of the exit slot.

9. In combination, a former device comprising a channel having an inlet opening for receiving a helical coil of wire, and means for turning the loops of wire laterally, and an exit slot of reduced Width, and pull mechanism for drawing wire loops through a former device, comprising a housing, spaced generally parallel shafts rotatably mounted in said housing, means for rotating said shafts, and resilient rolls on said shafts in adjacent contacting engagement.

10. A pull mechanism for drawing wire loops through a former device, comprising a housing, spaced generally parallel shafts rotatably mounted in said housing, means for rotating said shafts, resilient rolls on said shafts in adjacent contacting engagement, at least one of said shafts being also pivotally mounted in said housing and means for swinging the pivoted shaft to adjust the contacting pressure of said rolls.

11. A pull mechanism for drawing wire loops through a former device, comprising a housing, spaced generally parallel shafts rotatably mounted in said housing, means for rotating said shafts, resilient rolls on said shafts in adjacent contacting engagement, said shafts being also pivotally mounted in said housing, and means for swinging said shafts to adjust the contacting pressure of said rolls.

FLOYD 0. DE MILLAR. 

